AUTHORS: Devon C. Oliver, MNDNR; Loren Miller, MNDNR; Anthony Sindt, MNDNR; Cristian Hernandez, University of Minnesota
ABSTRACT: Redhorse species face a diverse array of impacts and conservation issues but often remain overlooked relative to their sportfish counterparts. Furthermore, they often lack constituency groups that advocate for their conservation. River Redhorse is a member of the Catostomidae family that have experienced reductions in abundance and range over the last century and are listed as critically imperiled in Kansas, New York, Louisiana, and Florida, imperiled in Wisconsin, Michigan, Virginia, and North Carolina, and vulnerable in Illinois, Indiana, West Virginia, Mississippi, and Georgia; additionally, they are listed as a species of special concern in Canada. Furthermore, like many potentially imperiled or vulnerable catostomid species, River Redhorse suffers from a paucity of demographic and life history information. Additionally, for River Redhorse, there is some ambiguity as to which morphological characteristics should be used to positively identify them relative to Shorthead and Greater Redhorse, which must be addressed first. Morphometrics and meristics used to determine species id can be highly variable, require harvest of the specimen, subjective, or are inconsistent in their determination across metrics both within and across different source material. To address this knowledge gap and to provide clarity in species identification for biologists and conservation hobbyists this study, 1) evaluated and compared morphometrics and meristics used to positively identify River Redhorse relative to Shorthead and Greater Redhorse, 2) determined useful morphometrics and meristics for identification of the three redhorse species within Minnesota based on genetically confirmed specimens.
